Muhammad and Allah put forth the proposition that asking hard questions can lessen the faith. In Quran 5:101-102 it is stated:"O you who have believed, do not ask about things which, if they are shown to you, will distress you. But if you ask about them while the Qur'an is being revealed, they will be shown to you. Allah has pardoned that which is past; and Allah is Forgiving and Forbearing.A people asked such [questions] before you; then they became thereby disbelievers."

Umar ibn al-Khattab (580-644), the second Caliph, came to kiss the Black Stone, he said in front of all assembled: "No doubt, I know that you are a stone and can neither harm anyone nor benefit anyone.Had I not seen Allah's Messenger (Muhammad) kissing you, I would not have kissed you." (Sahih Bukhari 1494)Now what precisely did Muhammad gain from kissing a rock?